Valve



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R. w.. @LEFFQRD VALVE Filed Sept. 6. 1929 Patented Nov. 17, 1931 ROGERW. CLIFFORD,- oF scnnnnjcrnfnrgnnw'onx rrr-ICE Application led SeptemberThis invention relates generally to valves and valve parts, and isespecially useful in piston distribution valves.

rilhe piston valves of usual practice, em-

a body two separately formed follower rings with spiders, one at eachend of the valve, and the valve rod extends entirely through the pistonelement and is provided with a shoulder which abuts one of thefollowers,

and a nut which abuts the other follower.

Such constructions, because of their excessive weight, produce rapidwearing of the packing and bull rings, the valve bushing, and theoperating gear, and because of the large number of parts which must bemachined and assembled, entail a high production cost.

An object of the present invention is to provide a piston distributionvalve, which has fewer parts, which is of less weight, which is moreeliicient, and which is more economical to manufacture, assemble, and

maintain than the piston valves heretofore known. The invention isespecially advantageous in distribution valves for high'speed engines,such as locomotives, as the vsubstantial reduction eected in the weightof the valve, lessens materially the inertia stresses, and theconsequent wear on the valve gear at high speeds.

ln the accompanying drawings: Figure 1 is a view, partly in longitudinalcentral vertical section, and partly in side elevation of a piston valveembodying the invention; Fig. 2, an end view, with a portion of theouter flange of the ring groove broken away, of the construction shownin Fig. 1; Fig. 3, a fragmentary transverse vertical section, on anenlarged scale, taken on the line III-HI of Fig. 2; Fig. 4i, afragmentary transverse vertical section, on an enlarged scale, taken onthe line IV-IV of Fig. 2; and, Fig. 5, an

enlarged fragmentary view showing details of the construction forpreventing the packinoj and bull rings from rotating.

n the practice of the invention, referring descriptively to the specificembodiment thereof which is herein exemplified, the piston valveembodies a tubular casting, 10, having a cylindrical piston portion,11', at each 6,'"192aserial No. 390,676.

end',- a-,cylii'idricallbodyfportion, l2, of less diameter thanithepiston portions, and connecting thesarne; and spaced. bosses, 13, for

vthe reception of a pin, 14, adapted to connect 'the valvetofthe end cfavalve rod (not shown). Each piston portion islfornied with inner andouter circularlanges, 1la,to provide-1a., circumferential groove, 11b,for the reception of a bull-ring, 15 and two split f packing rings, 16.I p y The bull ringswhich serve to seal the splits yin the packing ringsand to carry the weight ofthe valve, are substantially T-shape yin crosssection, having two lateralicircumferenti'al flanges, lapand 15b. Eachring prefo erably comprises a bottom section, 150, and an upper section,15d. The lower section is made greater than 18()Or of ay circle, so thatit will'vgrip the bot-tom of the. groove, 11b, to facilitate assemblingof the valve, and pre- .ventseparation ofthe endskof the ring segmentshen the bottomsection becomes worn. Therpaclring rings, .16,.areL-'shape in cross fsection,vand splitatla. LTo prevent the ,splitinjthepackingrings being brought into 7 l register rith the splitsv in thebullring, a pin, 17, is-,provided for each vpiston portion to 1,;prevent :relative turningof therings. Each pin passes through bores inthe piston flanges, f11a, grooves, 160, in the packing rings, and a.groove, 15e, in the lower section of the Vbull ring.

lir assembling therings in the grooves, the inner packing ring is firstapplied, the bull ring is next applied, its flange, 15b, being V85slipped under the inner packing ring, the outer packing ring is thenapplied. As the packing rings are made of sufficiently large crosssection to withstand steam pressure, they vwould be permanentlydistorted if; spread to pass over the bull ring.- To avoid suchspreading, the present invention pro- 'vides a construction whichenables the packing rings to be assembled by spreading them only asufficient amount to clear the outer.;v piston flanges.

lt will readily be appreciated that the improved construction efects amaterial reduction vin weight, machine work, and number of parts, overthe old construction hereinbe- 1.

limited to the particular embodiment dis-l closed, but includes suchchanges-and modif` ications as come Within the spirit and scope of theinvention as set oigtliill` the. appended claims. v

The invention claimed andl desired tobe securedV by Letters Patent is:

L.' The combination of a glrooved piston Y for valvesl and the like,having an integrally formedv flange comprising the outer-end wall of thegroove; and a transversely divided,

resilient sectionalbulil. ring hav-ing one Ofuqits sectionsgreaterthan180.4 o-fj'the ring andy one of its sections less than 180 of the ring,said' greater ring section deiining a Oap between its` ends that maybespread 'Within the elastic limits of the ring to a` sufficient exten-tfor mounting said section over said groove yin assembling the section,said ringl sections resting against the bottom 0E' te piston groove.

2; The combinationoiA a grooved piston for Y valves and the like, havingintegrally formed: iange, comprising? the outer end wall of the groove;and a transverselyy divided,

resilient sectionalI bul-l ring: substantially shaped `in cross-section,the head of the T 'V being at the inner'periphery of the ring andresting on. the bottom of the pistonl groove, Y

one section of the ring: being greater than 180" thereof andy onesection o v the ringfbeing lessv than. 180' thereof', and said greaterring section defining a gap between its ends that may be spread Withinthe elastic-limits-o'the ring to ka sufficient eXtentformountiiigsa-idsection over the groove in assembling the same.

ROGERz W. GLIFFRB.

